1. Technical Field
The present invention relates to a component feed apparatus for feeding components to a working machine such as a component mounting apparatus which sucks electronic components thereby mounting the components to a circuit board, and a method for feeding components with the apparatus.
2. Description of Related Art
A conventional component feed apparatus of a type referred to above is generally constituted as is disclosed in Japanese Unexamined Patent Publication No. 3-221326.
FIG. 4 shows the structure of a conventional component feed apparatus. In the apparatus, a first feed table 2 and a second feed table 3, capable of holding a plurality of component feed cassettes 1 thereon, are movably arranged on a rail 4. Each table is guided and supported by a driving means provided thereat to reciprocate in a direction of an arrangement of the component feed cassettes 1. Reference numeral 5 denotes a mounting head which sucks and carries the components in the component feed cassettes 1 for mounting on a board 7 that is positioned by an XY table 6.
In the thus-constituted apparatus, when component feed cassettes which contain the same kind of electronic components are respectively set to the feed tables 2, 3, one table can be switched to the other table on the occurrence of a shortage of components at the one table. In the meantime, components are replenished to the one table at which the component shortage has occurred. For instance, when components are being fed to the mounting head 5 from the first feed table 2 as indicated in the drawing, and if the first feed table 2 happens to be short of components, the first feed table 2 and the second feed table 3 are moved leftward in FIG. 4, then components are fed from the second feed table 3 to the mounting head 5 while components are replenished to the first feed table 2.
In the case where there are a variety of types of components to be used, different types of components are stored in feed cassettes 1 set to the feed tables 2, 3, so that the components are fed to the mounting head 5 through switching of the tables 2, 3.
As enhanced productivity is currently demanded without expanding a factory scale, the electronic component mounting apparatus alike is required to be improved in productivity per area and operation rate.
According to the above prior art apparatus, however, not only a component feed space F, but standby spaces G, H at both sides of the feed space F should be secured because of the linear side-by-side arrangement of the feed tables 2, 3 in the same direction as a board transfer direction x. This is an obstacle to shortening of a production line, i.e., enhancement in productivity per area.
Additionally, in the case where one feed table becomes short of components during the component supply, both feed tables are moved to position the other feed table at a component feed position, resulting in deterioration of component feed efficiency.
The present invention has for its object to provide an apparatus and a method for feeding components in a compact arrangement with high productivity.